No. To go into H4 status, she must either 1) enter the US with an H4 visa (only Canadian citizens are exempt from visas), which she must get at a US consulate abroad assuming she does not already have an H4 visa, or 2) do Change of Status to H4 status inside the US by filing I-539.Thanks for the prompt response.
My wife is in US now and she holds a TD status and Chinese passport. Can she go to POE to change the TD status to H4 visa diretly without filing I-535 and getting the approval?